Expressions and roles of key enzymes in serine synthesis pathway in NaAsO2-treated HaCaT cells / 环境与职业医学

Background The key enzymes of serine synthesis pathway (SSP) play an important role in tumor growth, proliferation, and invasion, but their roles in arsenic carcinogenesis are unclear. Objective To observe the effects of NaAsO2 treatment on the expressions of key enzymes [such as phosphoglycerate dehydrogenase (PHGDH), phosphoserine aminotransferase 1 (PSAT1), and phosphoserine phosphatase (PSPH)] of SSP and on the ability to proliferate and migrate in human immortalized skin keratinocytes (HaCaT) and NaAsO2-induced malignantly transformed HaCaT (T-HaCaT), and to explore the roles of SSP key enzymes in arsenic carcinogenesis. Methods (1) The T-HaCaT cells constructed earlier by our research team were divided into a passage control (0 μmol·L−1 NaAsO2) group, a T-HaCaT (0.5 μmol·L−1 NaAsO2) group, a NCT503 (PHGDH inhibitor, 25 μmol·L−1) group, and a NCT503 (25 μmol·L−1) + T-HaCaT (0.5 μmol·L−1 NaAsO2) group. Western blotting was used to detect the protein expression levels of SSP key enzymes in the passage control group and the T-HaCaT group. CCK8 assay and cell scratch test were used to detect the proliferation and migration rates of cells in each group respectively. (2) Well-grown logarithmic-phase HaCaT cells were treated with 0, 0.625, 1.25, and 2.5 μmol·L−1 NaAsO2 for 0, 24, 48, and 72 h to detect cell proliferation rate and protein expression levels of SSP key enzymes. In the subsequent experiment, HaCaT cells were pretreated with 25 μmol·L−1 NCT503 for 6 h, and then treated with 2.5 μmol·L−1 NaAsO2 for 72 h continuously. The experimental groups included a control (0 μmol·L−1 NaAsO2) group, an exposure (2.5 μmol·L−1 NaAsO2) group, a pretreatment (25 μmol·L−1 NCT503) group, and a pretreatment (25 μmol·L−1 NCT503) + exposure (2.5 μmol·L−1 NaAsO2) group, to detect the proliferation rate of cells in each group. Results The protein expression level of PHGDH in the T-HaCaT group were 1.60 times higher than that in the passage control group (P<0.05), and its proliferation rate (177.51%±14.69%) and migration rate (53.85%±0.94%) were also higher than the passage control group’s (100.00%±0.00% and 24.30%±2.26%) (both Ps<0.05), respectively. After the NCT503 intervention, the proliferation rate (144.97%±8.08%) and migration rate (35.80%±0.99%) of cells in the NCT503 + T-HaCaT group were lower than those in the T-HaCaT group (both P<0.05). The proliferation rate of HaCaT cells after NaAsO2 exposure for 72 h increased with the increase of exposure concentration (r=0.862, P<0.05), and consistently, the protein levels of SSP key enzymes in HaCaT cells in each exposure group were higher than those in the control group (all P<0.05). The proliferation rate of HaCaT cells treated with 2.5 μmol·L−1 NaAsO2 increased with the extension of exposure time (r=0.775, P<0.05), which was consistent with the changes of PHGDH levels in cells. After the NCT503 intervention, the proliferation rate of the pretreatment + exposure group was significantly lower than that of the exposure group (P<0.05). Conclusion The key enzymes of SSP may play an important role in the proliferation of T-HaCaT cells induced by NaAsO2.

The mutation of mitochondrial genome in lymphoma / 肿瘤研究与临床

Objective To investigate the mutation of mitochondrial genome in lymphoma. Methods The peripheral blood or borrow fluid 2 ml from 14 lymphoma patients in the First Hospital of Qinhuangdao between May 2016 and July 2017 were collected. Polymerase chain reaction (PCR) was used to amplify and sequence mitochondrial DNA, and the results were compared with the revised Cambridge reference sequence (rCRS) and human mitochondrial genome database (mtDB), and then the mutation was also analyzed. Results There were 118 mutation genes, including 57.63％ (68/118) in D-loop region, 18.64％ (22/118) in NADH dehydrogenase 5 (ND5) region, 13.56％(16/118) in cytochrome b oxidase (CbO) region, 5.08％(6/118) in ND1 region, 3.39％ (4/118) in cytochrome oxidase (COⅡ) region, 1.69％ (2/118) in ND4 region. Conclusion Mitochondrial DNA mutation in lymphoma has a high mutation rate.

Study on mitochondrial DNA mutation in patients with primary multiple myeloma / 白血病·淋巴瘤

Objective To study the mitochondrial DNA mutation in patients with primary multiple myeloma. Methods The mitochondrial DNA of 5 patients with primary multiple myeloma in the First Hospital of Qinhuangdao from February to June 2017 were amplified by polymerase chain reaction (PCR) and sequenced directly, and the results were compared with revised Cambridge Reference Sequence (rCRS) and Human Mitochondrial Gene Database (mtDB) database. Results There were 42 mutation genes, with 52.38％(22/42) mutation genes in D-loop region, 9.52％(4/42) mutation genes in ND4L region, 2.38％(1/42) mutation genes in ND5 region, 26.19％ (11/42) mutation genes in Cytb region, 7.14％ (3/42) mutation genes in ND1 region, and 4.76％ (2/42) mutation genes in COⅡ region. Conclusion There is a high mitochondrial DNA mutation rate in patients with primary multiple myeloma.

Analysis of mitochondrial DNA mutation in leukemia / 肿瘤研究与临床

Objective To study the mitochondrial DNA mutation in leukemia.Methods Mitochondrial DNA of 16 leukemia patients in First Hospital of Qinhuangdao from February to June 2017 were amplified and sequenced by using polymerase chain reaction (PCR).The result was compared with revised Cambridge reference sequence (rCRS) and human mitochondrial genome database (mtDB),and the mutation was also analyzed.Results There were 106 mutation genes in total,including 47.17 ％ (50/106) in D-loop region,2.83 ％ (3/106) in ND4 region,17.92 ％ (19/106) in ND5 region,22.64 ％ (24/106) in Cytb region,7.55 ％ (8/106) in ND1 region,1.89 ％ (2/106) in Co Ⅱ region.Conclusion There is a high mitochondrial DNA mutation rate in leukemia patients.

Risk Factors on Gas Gangrene after Open Trauma and Countermeasures / 中华医院感染学杂志

OBJECTIVE To explore the risk factors of gas gangrene after open trauma for its early diagnosis and precaution.METHODS The data of 42 patients with gas gangrene after open trauma from Aug 2003 to Aug 2008,were collected.The risk factors of gas gangrene after open trauma had been retrospectively analyzed from the cause of the injuries,the distribution of latent period,wound,systemic symptoms,laboratory examination and treatment.RESULTS Gas gangrene after injury was related with open wounds for various reasons.Latent period of gas gangrene was 24-72 h.Early risk factors of gas gangrene among them mainly included degloved or avulsed skin-injury(100%),musce trauma(100.00%),contaminated wound and retained foreign bodies(95.24%),weak pulse of peripheral artery(95.24%),nervous injury(90.48%),and lower temperature of skin aound the wound(83.33%).There were obviously systemic symptoms in infective stage but in early stage were not.CONCLUSIONS Gas gangrene is extremely rare in injury patients but it is life-threatening.So more attention should be paid to the risk factors in order to decrease the incidence of gas gangrene after trauma.Improving the prognosis of patients;the wounded locations should be effectively treated early so as to improve the prognosis.